• Title/Summary/Keyword: Component development

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The a-Si:H/poly-Si Heterojunction Solar Cells

  • Kim, Sang-Su;Kim, do-Young;Lim, Dong-Gun;Junsin Yi;Lee, Jae-Choon;Lim, Koeng-Su
    • Journal of Electrical Engineering and information Science
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    • v.2 no.5
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    • pp.65-71
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    • 1997
  • We present heterojunction solar cells with a structure of metal/a-Si:H(n-i-p)/poly-Si(n-p)/metal for the terrestrial applications. This cell consists fo two component cells: a top n-i-p junction a-Si:Hi cell with wide-bandgap 1.8eV and a bottom n-p junction poly-Si cell with narrow-bandgap 1.1eV. The efficiency influencing factors of the solar cell were investigated in terms of simulation an experiment. Three main topics of the investigated study were the bottom cell with n-p junction poly-Si, the top a-Si:H cell with n-i-p junction, and the interface layer effects of heterojunction cell. The efficiency of bottom cell was improved with a pretreatment temperature of 900$^{\circ}C$, surface polishing, emitter thickness of 0.43$\mu\textrm{m}$, top Yb metal, and grid finger shading of 7% coverage. The process optimized cell showed a conversion efficiency about 16%. Top cell was grown by suing a photo-CVD system which gave an ion damage free and good p/i-a-Si:H layer interface. The heterojunction interface effect was examined with three different surface states; a chemical passivation, thermal oxide passivation, and Yb metal. the oxide passivated cell exhibited the higher photocurrent generation and better spectral response.

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Management Plan on EMC for Functional Safety of the ISO26262 (자동차 기능 안전성(ISO26262)에 관한 EMC 관리계획)

  • Shin, Jaekon;Chung, Yeonchoon;Choi, Jaehoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.25 no.10
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    • pp.1020-1027
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    • 2014
  • ISO 26262 is applied to vehicle and electrical/electronic component manufacturers for minimizing car accidents and life damage by the extended use of electronic control equipments and their malfunctions. In this standard, safety requirements are required to be applied from the early stage of development upto manufacture and disposal stages throughout the total lifecycle of the full vehicular system, and electromagnetic compatibility must be also managed as an important consideration factor. Therefore, it is nowadays very necessary to research and develop EFS(EMC for Functional Safety) to be applied in each stage of the design, manufacture, accreditation, use, maintenance stages of cars. In this paper, how EFS can be applied for the application of ISO 26262 is described. By the enforcement of this suggestions into the legal requirement or New Car Assessment Program(NCAP) test items, it is necessary that car manufacturer have to perform some procedures for ensuring car safety by themselves.

The Development of Quantitative Audit System for Safety Management Systems based on Accident Database (사고 데이터베이스를 활용한 안전 관리 시스템의 정량적 Audit 시스템 개발)

  • Ahn, Sung Joon;Lee, Chang Jun
    • Journal of the Korean Society of Safety
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    • v.28 no.1
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    • pp.40-46
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    • 2013
  • In the chemical process industries, accidents have a high potential and large effects on catastrophic results. Therefore the safety management for accident prevention plays a crucial role to guarantee the process safety. For these reasons, many systematic methods for safety management system have been widely employed in the fields of chemical processes. PSM (Process safety management) is one of most representative methods. The audit system, which is one of PSM system components, evaluates the performance of PMS system. However, most existing safety audit systems are not systematic and these are performed based on knowledges and experiences of various specialist. Moreover, the safety audit is only performed based on each independent technical component. So, the results of safety audit are not a quantitative index but only a series of commentaries. Finally, it is very difficult to obtain the comparison with other plants or industries. In this study, the novel systematic method and index-based accident database of auditing safety management systems for quantitative assessment are proposed. First, the elements of safety audit replace technical methods to categories of accident database. The F-N curve of each category for accident database is employed to derive the index for quantitative assessment. The Accidental Factor Risk Index (AFRI) is suggested for evaluating the effect of each element in accident database and safety audit system. The safety audit can be modified according to the proposed index.

The Types and Characteristics of the Male Nurses Perceived by Female Nurses : An Application of Q- Methodology (여자간호사가 인식하는 남자간호사의 유형 및 특성 : Q 방법론적 접근)

  • Seong, Ji-Suk;Yeom, Eun-Yi
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.1
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    • pp.572-584
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    • 2016
  • The aim of this study was to identify the female nurses' perception of the types and characteristics of male nurses using Q-methodology, which can explore human subjectivity. The 35 selected Q-statements from each of 35 subjects were classified into a normal distribution using a 9 point scale. The collected data was analyzed using the PC-QUANL program. Principal Component Analysis identified 3 types of perception toward male nurses. Type 1 was classified as 'development-oriented support type', Type 2 was classified as 'realistic critical type', and Type 3 was classified as 'conservative acceptance type'. The consensus of opinion in each type was 'Male nurses are under stress due to the unique characteristics of a female-dominated workplace'. These results will contribute to the perception improvement of female nurses toward male nurses by developing arbitration programs based on the three types.

Effects Quality Characteristics and Development of Global Sauce using Traditional Gochujang (세계적 소스류의 품질특성 다양화를 이용한 고추장소스개발)

  • Cho, Kyung-Hyun;Kang, Soon Ah
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.11
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    • pp.8089-8095
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    • 2015
  • Gochujang, a kind of fermented red pepper paste with soybean koji, is a traditionally using spices in Korea and is characterized by its special taste in combination with hot, sweet and salty taste, and its component are consist of protein, carbohydrates, capsanthin and capsinoids, vitamin and other minor components. We tried to develop Gochujang sauce characterized by mild hot and spicy taste, proper viscosity and its strong application to steak, fried food, pizza and others. Gochujang sauce tended to show strong red color and lightness as pH decreases and Paprica oleoresin improved a value to 12.11 and L value to 24.24 which is similar to tomato paste 1:1-1.5:1 ratio of Gochujang and tomato paste was evaluated to be acceptable in the aspect of Gochujang's characteristics.

Design and Implementation of Version Control System for Meta Information Management of Source Codes (원시코드의 메타 정보 관리를 위한 버전 제어 시스템의 설계와 구현)

  • Oh, Sang-Yeob;Chang, Duk-Chul
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.3
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    • pp.633-648
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    • 1998
  • Rapid computing environment, change of the application structure, and various user demand will increase the demand of the software development. Version control is helpful to improve productivity using delta, and useful to establish component from existing data of source code. This paper presents the design and implementation of the version control system. which is composed of retrieval system and delta management system. In retrieval system, vanous retrieve methods arc proposed. This methods provides the process methodology with filename, content, size and date. Various retrieve methods arc important for the effective delta management. Meta data can be easily composed for the delta management by these methods. Compared with other systems, this implemented version control system has some advantage. First, for delta management, version maintenance for delta management becomes easier by integrating the forward and back-ward methods. Second, delta managent part of a project is to unite the forward and backward method. the effieiency of this system is to increased in management. Also, this system supports a thechnique of using the database and files for project repository and makes the version management more effective.

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Performance Improvement of Traffic Signal Lights Recognition Based on Adaptive Morphological Analysis (적응적 형태학적 분석에 기초한 신호등 인식률 성능 개선)

  • Kim, Jae-Gon;Kim, Jin-soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.9
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    • pp.2129-2137
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    • 2015
  • Lots of research and development works have been actively focused on the self-driving vehicles, locally and globally. In order to implement the self-driving vehicles, lots of fundamental core technologies need to be successfully developed and, specially, it is noted that traffic lights detection and recognition system is an essential part of the computer vision technologies in the self-driving vehicles. Up to nowadays, most conventional algorithm for detecting and recognizing traffic lights are mainly based on the color signal analysis, but these approaches have limits on the performance improvements that can be achieved due to the color signal noises and environmental situations. In order to overcome the performance limits, this paper introduces the morphological analysis for the traffic lights recognition. That is, by considering the color component analysis and the shape analysis such as rectangles and circles simultaneously, the efficiency of the traffic lights recognitions can be greatly increased. Through several simulations, it is shown that the proposed method can highly improve the recognition rate as well as the mis-recognition rate.

Effect of Crystal Form on Bioavailability (결정형이 생체이용률에 미치는 영향)

  • Sohn, Young-Taek
    • Journal of Pharmaceutical Investigation
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    • v.34 no.6
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    • pp.443-452
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    • 2004
  • Habit is the description of the outer appearance of a crystal. If the environment of a growing crystal affects its external shape without changing its internal structure, a different habit results. Crystal habit and the internal structure of a drug can affect bulk and physicochemical properties, which range from flowability to chemical stability. A polymorph is a solid crystalline phase of a given compound resulting from the possibility of at least two different arrangements of the molecules of that compound in the solid state. Chemical stability and solubility changes due to polymorphism can have an impact on a drug's bioavailability and its development program. During crystallization from a solution, crystals separating may consist of a pure component or be a molecular compound. Solvates are molecular complexes that have incorporated the crystallizing solvent molecule in their lattice. When the solvent incorporated in the solvate is water, it is called a hydrate. To distinguish solvates from polymorphs, which are not molecular compounds, the term pseudopolymorph is used. Identification of possible hydrate compounds is important since their aqueous solubilities can be significantly less than their anhydrous forms. Conversion of an anhydrous compound to a hydrate within the dosage form may reduce the dissolution rate and extent of drug absorption. An amorphous solid may be treated as a supercooled liquid in which the arrangement of molecules is random. Amorphous solids lack the three-dimensional long-range order found in crystalline solids. Since amorphous forms are usually of higher thermodynamic energy than corresponding crystalline forms, solubilities as well as dissolution rates are generally greater. A study on crystal form includes characterization of (l)crystal habit, (2)polymorphism, (3)pseudopolymorphism, (4)amorphous solid.

GIS- Based Predictive Model for Measure of Environmental Pollutant (GIS를 이용한 환경오염의 예측 모델)

  • Lee, Ja-Won
    • Journal of the Korean association of regional geographers
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    • v.14 no.2
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    • pp.114-125
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    • 2008
  • Colored dissolved organic matter(CDOM) is an important component of ocean color that can be used as an invaluable tool in water quality and ocean color studies. With the largest source of coastal CDOM appearing to be from freshwater discharge into the ocean, coastal predictive models will do much to refine our knowledge about major processes that control CDOM distributions in coastal waters and provide a better insight into the global carbon cycle. This study aims at developing a GIS-based watershed-scale predictive model of CDOM distributions in Neponset river watersheds that can be used to appraise our understanding of CDOM sources and distributions in coastal waters and predict the response of CDOM concentration to changes in land use patterns. Weighting factors are developed for CDOM freshwater sources after extensive groundtruthing from various landuse types in the watershed. This model makes use of a publicly available DEM(Digital elevation model) as the base data for analysis. Stream networks, discharge, and land use data are used from public repositories while sub- watershed delineation, pour-points, and land use parcels are generated using Spatial Analysis of ArcGIS 9.2 to estimate the CDOM loading from various sources to the lower tributaries of rivers. The Neponset Watershed in eastern Massachusetts is selected as the site for development of the model.

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Establishment and Application of Computer-Assisted Environmental Information System for Land Use Zoning and Environmental Analysis of Natural Park (자연공원의 환경분석 및 용도지역설정을 위한 전산환경정보체계의 수립과 적용)

  • Lee, Myung-Woo
    • Journal of Environmental Impact Assessment
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    • v.2 no.1
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    • pp.39-55
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    • 1993
  • The importance of urban and regional natural park increases because of the needs for preserving the natural resources and providing with natural recreation space in nature. This planning of natural park management should be established based on the research of the various natural resources in the park. But for the lack of effective data synthesizing methods and concepts, only some restricted factors for zoning plan are considered even though GIS computer system for large complex simulation is used. Therefore, in this study three ecological zoning models such as Basic Factor Model (BFM), Visual Landscape Model (VLM) and Comprehensive Ecological Model (CEM) are proposed and applied to Byounsan Peninsula Nature Park(BPNP) for comparison with the current natural park zoning. The BFM has three components -elevation, slope and vegetation. The VLM has applied with six components -elevation, slope, vegetation, road type, and the visual distance. Finally the CEM's modelling factors have included all of BFM, VLM components are added with the land use type, nature and historic resource factors. The zoning concept of BPNP was based on "Minimization" focused on the specific factors. But introduced modelling concept is "Optimization" based on the total ecological environment. So the result of the modelling has larger area for preservation and development zoning compared with the current zoning whose characteristics are ambiguous which allows the environmental destruction. The future study issues will be the determination of the weighting factor, component reconsideration based on the ground truth data and the agriculture residential area zoning.

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